$ { \left[\begin{array}{rr}{4} & {-2} \\ {-1} & {4} \\ {1} & {0}\end{array}\right]-\left[\begin{array}{rr}{0} & {1} \\ {-1} & {-2} \\ {0} & {-1}\end{array}\right] = {?} } $
Explanation: To find the difference of two matrices, subtract the corresponding items between each matrix. ${\left[\begin{array}{rr}{4}-{0} & {-2}-{1} \\ {-1}-{-1} & {4}-{-2} \\ {1}-{0} & {0}-{-1}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{4} & {-3} \\ {0} & {6} \\ {1} & {1}\end{array}\right]}$